docs: def register_check(self, section=None, *args, **kwds):
      """
      Usage:
      # register in default section
      @profile.register_check
      @check(id='com.example.fontbakery/check/0')
      def my_check():
        yield PASS, 'example'
  
      # register in `special_section` also register that section in the profile
      @profile.register_check(special_section)
      @check(id='com.example.fontbakery/check/0')
      def my_check():
        yield PASS, 'example'
  
      """
      if section and len(kwds) == 0 and callable(section):
        func = section
        section = self._default_section
        return self._add_check(section, func)
      else:
        return partial(self._add_check, section)